What Is Answer Engine Optimisation (AEO)? A Founder's Guide

Answer engine optimisation (AEO) is the work of making a website easy for AI assistants such as ChatGPT, Perplexity, Claude and Google's AI Overviews to find, understand and cite. It builds on SEO: pages still need to be crawlable and indexed. AEO adds specific, self-contained claims a model can quote and attribute to a named source.

That definition is simple. The practice around it is not, because most of what's sold as AEO right now is either rebranded SEO or tricks that don't survive contact with how these systems actually retrieve sources. This guide covers what answer engine optimisation is, how AI assistants pick what to cite, what changes compared with SEO, and what a founder should actually do about it.

What is answer engine optimisation?

Answer engine optimisation is the practice of structuring a website's content, technical setup and wider web presence so that AI-driven answer engines cite it when people ask questions the business should be the answer to. It's spelled "answer engine optimization" in American English, and it overlaps with terms like generative engine optimisation (GEO) and AI search optimisation. The labels differ. The goal is the same.

An answer engine is any system that responds to a question with a written answer rather than a list of links. ChatGPT with search, Perplexity, Claude with web search, Microsoft Copilot and Google's AI Overviews and AI Mode all work this way. Most of them still show sources. AEO is about being one of those sources, and about the answer describing your business accurately when it does.

The shift matters because the buyer's behaviour has changed. A founder looking for a supplier used to search, scan ten blue links and click three. Now many of them ask an assistant, read one synthesised answer, and click the one or two sources that answer seems to rest on. Being on page one is still necessary. It is no longer the same as being seen.

How do AI assistants decide what to cite?

AI assistants with search generally work in two stages: they retrieve candidate pages from a search index, then they write an answer and link to the pages they drew on. AEO affects both stages.

Retrieval depends on crawling and indexing. Each assistant relies on an index built by a crawler:

• Google says a page must be "indexed and eligible to be shown in Google Search with a snippet" to appear as a supporting link in AI Overviews or AI Mode (Google Search Central, "AI features and your website").
• OpenAI says its OAI-SearchBot crawler "is used to surface websites in search results in ChatGPT's search features", and recommends allowing it in robots.txt (OpenAI, "Overview of OpenAI crawlers").
• Perplexity documents an equivalent crawler, PerplexityBot, for surfacing sites in Perplexity's search results.

If those crawlers can't reach your pages, nothing else in this guide matters.

Citation depends on what's on the page. Once a page has been retrieved, the model has to decide whether it actually supports a sentence in the answer. None of these companies publish exactly how that choice is made, so anyone claiming to know the formula is guessing. What can be observed is consistent: pages that state a clear, specific answer near the top, in plain sentences, get quoted. Pages that circle a topic in general terms get skipped, because there's nothing precise in them to attribute.

Is AEO different from SEO?

AEO is mostly SEO with less tolerance for vagueness. The technical foundations are the same, and Google says so directly: there are "no additional requirements to appear in AI Overviews or AI Mode, nor other special optimizations necessary", and "there's also no special schema.org structured data that you need to add" (Google Search Central).

Google's own advice for AI search is the advice it has always given. John Mueller of Google's Search Relations team wrote that site owners should "focus on making unique, non-commodity content that visitors from Search and your own readers will find helpful and satisfying" (Google Search Central Blog, May 2025).

So what actually changes? Three things.

1. Ambiguity stops being survivable. A page could rank on a classic results page while saying very little, because the click decided the rest. An answer engine reads the page for you. If it can't extract a clear claim, it uses someone else's.
2. The unit of competition shrinks. SEO competes page against page. AEO competes sentence against sentence. The question is whether any single sentence on your page is the best available answer to part of the question.
3. Your reputation off-site counts more. Assistants synthesise from multiple sources. If your site says one thing and directories, reviews and profiles say another, the answer reflects the confusion.

Alchelyst's position is that AEO is not a new discipline bolted onto SEO. It's SEO that finally punishes having nothing specific to say.

What makes content citable by AI assistants?

Content gets cited when it contains sentences that answer a question completely on their own and are clearly attributable to a named source. These are the patterns that make that happen:

• Answer first. Put a 40 to 60 word direct answer at the top of the page, under the heading, before any context. This article opens that way on purpose.
• One claim per sentence. "Alchelyst's Core engagement takes two weeks" can be quoted. "Our flexible, collaborative process adapts to each client's timeline" can't.
• Name the entity. Write "Alchelyst recommends" or "Google says" rather than "we think" or "it is". A sentence lifted out of context still needs to say who's speaking.
• Ask the real question in the heading. Headings phrased as the questions buyers type, such as "How much does brand strategy cost?", map cleanly onto how people prompt assistants.
• Source every number. A statistic with a named source and a link is more likely to be repeated than one floating on its own, and less likely to come back as a misquote.
• Say something a competitor wouldn't. If ten pages say the same thing, an assistant has no reason to pick yours. A specific position is the most reliable way to be the source.

That last point is where AEO meets brand strategy. A model can only cite a claim you've actually made. Businesses that haven't decided what they believe end up publishing category-average content, and category-average content is exactly what an answer engine can produce without citing anyone. That's why Alchelyst treats a values-first brand position as the starting point for AEO, not an optional extra.

A before-and-after example

Illustrative example, not a client. A landscaping company's service page reads: "We offer comprehensive landscaping solutions tailored to your unique needs, with a commitment to quality and customer satisfaction."

An assistant asked "Which landscapers in the Fraser Valley install native plant gardens?" can't use that sentence. It names no service, no place and no claim.

Rewritten, using a placeholder name: "Acme Landscaping designs and installs native plant gardens in Abbotsford, Chilliwack and Langley. Every planting plan uses species native to the Lower Mainland, and the company does not install lawn."

Those sentences can be quoted, and the last one is a position a competitor might disagree with.

What technical work does AEO need?

The technical side of answer engine optimisation is short, and most of it is standard SEO hygiene. Here is the checklist Alchelyst runs on every site:

1. Allow the search crawlers. Check robots.txt allows Googlebot, OAI-SearchBot and PerplexityBot. Blocking GPTBot is a separate decision: OpenAI says GPTBot is used for model training and that blocking it does not remove you from ChatGPT search.
2. Get indexed. Submit a sitemap in Google Search Console and Bing Webmaster Tools, and fix pages excluded from the index.
3. Use one canonical host. If your site answers on both www and the bare domain, pick one and redirect the other. Split signals weaken every page.
4. Add structured data that matches the page. Organization, Article, BreadcrumbList and FAQPage schema help machines read the page. Google's guidance is that markup must match the visible text, so schema describing content that isn't on the page works against you.
5. Make key facts plain text. Prices, locations, services and contact details should be readable HTML, not text inside images or behind scripts.

Notice what isn't on that list. Google says you don't need special AI text files or markup to appear in its AI features. Files like llms.txt may become useful for other assistants, but none of the major ones have documented relying on them, so they shouldn't be anyone's priority.

Why do entities and consistency matter?

An entity is a distinct thing a search system can identify: a business, a person, a place, a product. Answer engines describe entities by combining what they find about them across the web. Consistency across those sources decides whether the description is accurate.

For a small business, entity work is practical rather than technical:

• The business name, address, phone and email are identical on the website, Google Business Profile, LinkedIn and directories.
• The founder is named on the site and linked to the business everywhere they appear.
• The description of what the business does is the same specific sentence everywhere, not five loosely related taglines.

Schema markup makes those facts machine-readable, but schema can't create consistency that isn't already there. If an assistant gets your business wrong, the fix is usually in the sources it's reading, not in the prompt.

How do you measure answer engine optimisation?

AEO is measured by asking the questions your buyers ask and recording what comes back. No analytics tool currently captures every AI answer that mentions a business, so manual checks remain the most direct measure.

A simple monthly routine:

1. Write down ten to twenty questions a buyer would ask before hiring you, in their words.
2. Ask each one in ChatGPT, Perplexity, Google (noting any AI Overview) and Claude.
3. Record whether you're mentioned, whether you're linked, and whether the description is accurate.
4. Check your analytics for referral traffic from AI assistants, such as visits from chatgpt.com or perplexity.ai.

Track the same questions every month. The trend matters more than any single answer, because AI responses vary between sessions.

What can't AEO do?

Answer engine optimisation can't guarantee citations. No agency controls what an AI assistant says, and anyone promising a guaranteed placement in ChatGPT is selling something they can't deliver.

AEO also can't fix having nothing to say. If your positioning is interchangeable with your competitors', making it more legible to machines just makes the sameness easier to read. The order Alchelyst works in is fixed for this reason: decide what the business believes, then make that belief the clearest answer on the web.

Does a small business need answer engine optimisation?

A small business needs AEO if its buyers research before they buy, and most do. The more considered the purchase, the more likely the buyer is to ask an assistant to compare options, explain a term or shortlist suppliers. Those are exactly the questions a small business can win, because they're specific and local and the big players don't bother answering them well.

You likely need help if:

• Your site ranks but you can't find yourself in AI answers to your buyers' questions.
• AI assistants describe your business inaccurately, or describe a competitor when asked about you.
• Your content is written around keywords rather than the questions buyers actually ask.
• Nobody has checked your robots.txt, schema or canonical setup since the site launched.

Alchelyst's SEO / AEO service works backwards from the questions your buyers type and ask: intent mapping, technical and on-page fixes, entity and schema work, citable claim structuring, and monitoring how AI assistants describe you. If you're comparing providers, here's what AEO services should include, and the red flags. The first step with Alchelyst is a strategy call where we look at what assistants say about you today.

Frequently asked questions

Is AEO the same as GEO?

Mostly, yes. Answer engine optimisation (AEO) and generative engine optimisation (GEO) both describe making content easy for AI systems to find, understand and cite. GEO is sometimes used more narrowly for generative AI answers, while AEO also covers featured snippets and voice answers, but in practice the work overlaps almost entirely.

Do I need an llms.txt file for AEO?

Not for Google. Google states that you don't need new machine-readable files, AI text files or special markup to appear in AI Overviews or AI Mode. An llms.txt file is low effort and harmless, but it should come after crawlability, indexing and clear content.

Does schema markup guarantee AI citations?

No. Schema markup helps AI systems and search engines read facts about a page, but it doesn't guarantee a citation. Google's guidance is that structured data must match the visible text on the page. Citations depend mainly on whether the content clearly answers the question.

Should I block GPTBot to protect my content?

That's a separate decision from AEO. OpenAI says GPTBot is used for training its models and OAI-SearchBot is used for ChatGPT search. You can block GPTBot and still allow OAI-SearchBot, which keeps your site eligible to appear in ChatGPT search results.

How long does AEO take to work?

Technical fixes such as unblocking crawlers can take effect within days. OpenAI notes robots.txt changes can take about 24 hours to be reflected. Content and entity changes take longer, because assistants have to re-crawl pages and other sources have to catch up. Expect to measure progress over months, not weeks.